Circuit controlling device



wwmsz .Fufly 18, 1933. K, BECKER CIRCUIT CONTROLLING DEVICE Filed March 5, l93l Inventor: KLLT'IU Becker;

His Acbor-neg.

Patented July 18, 1933 UNITED STATES PATENT OFFICE xuRir iancizrm, or :BERLIN-wanna:ow, GERMANY, ASSIGNOR To GENERAL ELRc'rRIc oomtr NY, A CORPORATION OF NEW YORK CIRCUIT CONTROLLING DEVICE i Application flled March 5, 1931, Serial No..

, control and timeelement undervoltage pro- 520351, and in Germany Mafrch 12, 1930.

contacts also for manual control to efl'ect the. unretarded disconnection of the machine, then the difliculty is encountered that after a manual operation lasting only a short time the heat element has notcooled down and in consequence the contacts will return again into their original position so that the machine again becomes connected. In order to avoid this difliculty, according to the inven- 1| the system. In order to avoid needless disi which after the failure of the voltage open tobe heated by a heating winding which is i contacts remain closed for a. short time. If,

tion, the switch is arranged so that in case of manual operation, a pawl, tension spring, or the like is actuated to hold or lock the switch contacts in the open position. In order that the locking may be securely efi'ected, special interrupting contacts are arranged upon the actuation of which the lockin deevery short failure of the voltage, the undervice is brought into its position for 100 g voltage protective switches for the machines the main switching-in contacts. To permit have beenprovided with mechanical devices reswitching in, the arrangement is so made that with the actuation of the switchingin contacts the locking is released. In the drawing the single figure shows diagrammatically a combined manual and I undervoltage time element switch embodying the invention. In this case the combined'lfi manual and undervoltage switch is not ifr tended to connect and disconnect the machine directly but by means of the switch magnet a. By means of the present invention, the The switch is represented in its disconnect- 30 requirements of simplicity, smallness and ed position as occurs when the switch has also adjustability for a switch with automatic opened automatically in response to underundervoltage time element release on voltvoltage conditions. The switching-in cona e are fulfilled by arranging for opening tacts d are open and the disconnecting con- 05 closing the switch contacts with delay by tacts d are closed. The switching-in contacts d and the disconnecting contacts d 35 means of the change in. temperature of a thermal element, for example, of a bimetallic fare connected with one another by individual members in such a manner that when the disstrip, hot wire or the like in response to undervoltage conditions. The thermal element connecting contacts are closed the switchingin accordance with'the invention is arranged in contacts can be opened and losed independently of them. The switching-in conenergized responsively to the'system voltage. tact d carried on the bimetallic th'ermal ele- In the fully heated condition the thermal ele- \ment. 71/ is electrically iiisulated therefrom as ment maintains the, contacts closed and upon indicated in the drawing and the disconnectthe occurrence of undervoltageconditions, the ing contact d carried on the spring member f also may be insulated therefrom in a similar manner. L

In operation the push button 0 is pressed, so that the contacts d become closed. Thereby a circuit is established from 9+ through the heating winding g for the bimetallic 10 tective switch.

It has been proposed heretofore to provide switches for electric machines with an undervoltage release, so that with .the absence of voltage the machine is disconnected from connection of the machines in the case of the connecting contacts only after the running down of a clock mechanism adjusted to a predetermined time. If the voltage returns within this time, then the machine remains connected. Such clock mechanism timing devices are very complicated, large and expensive, especially if the running -down time is long.

during this time, the voltage returns to normal then the machine remainsconnected, but otherwise it is disconnected from the system.

Where it is desired to use thesame switch necting contacts al to 'contacts al be again opened. The current pressknob c,

for the switch magnet then flows through the self-holding contacts I; in place of through (Z However, soon after the switching-in, the bimetallic spring h is heated by the heating winding 9 in such a manner that it snaps over and closes again the switching-in contacts (Z Now, if the actuating voltage is absent for a short time, then the heated bimetallic spring holds the contacts d closed and the magnet a remains connected. If, however, the voltage is absent for a longer period, then the bimetallic spring cools down and opens the switching-in contacts al with a snap movement. Since with the absence of the voltage the self-holding contactsb of the switch magnet a open, upon the. return of the voltage there is no exciting circuit for magnet 11 so that the switching-in has to be effected anew. By means of the adjustment 6 the tension of the bimetallic spring inay be varied so as to control the period required to effect the snapping over. In this way the time can be varied within .wide limits.

If the switch magnet a is to be disconnected without retardation, push knob i is pressed. Thereby the spring f is brought into the position indicated by the broken lines and the disconnecting contacts d are opened. The disconnecting and switching-in contacts are coupled with one another through a connecting member at in such a manner that with the opening of the disconnecting contacts, the connecting member is also raised and thereby the switching-in contacts d areopened. Through the opening of d and al the switch magnet a is disconnected. The spring 7 is bent in such a manner that it has two stable positions of rest, the one position is indicated in full-lines and the other in broken lines. After the release of push knob 2', the spring f remains in its second stable position in which its energy is suflicient to act in opposition to the energy of the heated bimetallic spring h and it is thus 'ableto keep the switching-in contacts open. lVith the reswitching-in by pressing the the spring 7 is also brought back again into the first stable position. The opening and closing of the connecting and disconnecting contacts need notbe effected bya snap movement as described but can take place steadily. Also, if desired, the heating Winding'can be connected to an appropriate transformer (bell transformer) or the element be heated in any other suitable manner.

The spring and the bimetallic spring k of then the disconnecting aeiaoea when the thermal element becomes heated and for controlling the opening of the switch with a time delay dependent upon the cooling of the thermal element, and means for opening the switch instantaneously and maintaining the same open independently of the time delay control of the thermal element.

2. In a circuit controlling device, the combination of a switch, a thermal element for operating the switch from a predetermined position to another position when the thermal element becomes heated and for returning the switch to said predetermined position with a time-delay dependent upon the cooling of the thermal element, heating means for the thermal element controlled by the switch, and means for operating the switch to and maintaining the same in said predetermined position independently of the control of the ther-' mal element.

3. A time element undervoltage circuit protective device comprising a switch, a thermal element for holding the switch closed when the thermalelement becomes heated and for controlling the opening of the switch with a time delay dependent upon the cooling of the element, anelectrical heating means for the thermal element connected to be energized responsively to the voltage of the circuit upon the closure of the switch, and means for opening the switch and maintaining the same open independently of the control of the thermal element.

4. A time delay undervoltage circuit protective device comprising .a control switch, manual means for closing said switch, a thermal element for biasing the switch to the closed position when the thermal element becomes heated and for controlling the opening of the switch with a time delay dependent upon the cooling of the element, electrical heating means for the thermal element connected to be energized responsively to the voltage of the circuit upon the closure of the switch, and manually operable means for opening the switch and maintaining the same open independently of the control of the thermal element. p

5. A time element undervoltage circuit protective device comprising a control switch, manual means for closing the switch,'a thermal element for biasing the switch to the Closed position when the thermal element bean electromagnetic switch protective device comprisin comes heated and for controlling the opening of the switch with a time delay dependent upon the cooling of the element, heating means for the thermal element connected to be energized responsively to the voltage of the circuit upon the closure of the switch,

connected to be energized upon the closure of the control switch for maintaining said heating means energized, and manually operable means for open-' ing the control switch and maintaining the same open independently of the control oi":

the thermal element.

' 6. In a circuit controlling device, the combination of a switch, a thermal element for operating the switch from a predetermined position to another position when the thermal element becomes heated and for returning the switch to said predetermined position upon the cooling of the thermal element, means for operating the switch from said predetermined position to said other position independently of the thermal element and means for operating the switch to and maintaining the same in said predetermined position independently of the control ot'the thermal element. x

7. In a circuit controlling device, the combination of a switch, a thermal element for biasing the switch to the closed position when the thermal element becomes heated and for controlling the opening of the switch upon the cooling of the element, means efiective upon the closing of the switch for heating the thermal element, means independent of the thermal element for closing the switch, and means for opening the switch and maintaining'the same open independently of the control of the thermal element.

8. A time element undervoltage circuit a thermal responsive switch having an e ect-rical heating coil, means for closing the switch independently of the operation of the heating coil, an electromagnetic switch connected to be energized upon closure of the thermal switch and having contacts connected to establish an energizing circuit for said heating coil to ren-' der said thermal switch efiective to control the deenergization of the electromagnetic switch with a time delay dependent upon the cooling of. said thermal switch responsively to a sufiicient drop in the voltage of said energizing circuit to reduce the heating efl'ect of said heating coil, and a switch-for deenergizingsaid heating coil independently of said drop in voltage.

' 9. A' time element undervoltage circuit protective device comprising an electromagnetic switch, a normally open control switch operable to the closed posit-ion to establish an energizing circuit for the electromagnetic switch, a thermal responsive element having electrical heating means connected to be heated upon closure of the magnetic switch energizlng circuit for the electromagnetic switch, a thermal responsive element having 3 electrical heating means connected to be heated upon closure of the magnetic switch for biasing the normally open control switch to the closed position and maintaining the same therein responsively to the voltage of the energizing circuit of the electromagnetic switch, a normally closed control switch connected in the heating circuit of said thermal element and having means for biasing the switch to the open position upon operation thereto, and means associated with said normally open control switch for operating the second control switch to the closed position upon closure of said first control switch.

11. In a circuit controlling device, the, combination of a switch, an electrically heated thermal element for operating the switch between two positions dependent upon the heating and cooling of the thermal element, a second switch for controlling the heating and cooling of the thermal element, and connec' tions between the said switches whereby uponthe opening of the second switch, the first switch is opened and upon the closure of the first switch, the second switch is closed. 12. In a circuit controlling device, the combination of a switch, a thermal element for operating the switch, a second switch me chanically connected with the first switch to be operated to the closed position when the first switch is closed, means for closing the first switch independently of the operation of the thermal element, and an electrical heating circuit for the thermal element jointly controlled by the two switches.

13. In a circuit controlling device, the, combination of a switch, a thermal element for operating the switch, a second switch mechanically connected with the first switch to be operated to the closed position when the first switch is closed, means for closing the first switch independently of the operation of the thermal element, and an electrical heating circuit for the thermal element jointly controlled by the two switches and having first switch.

KURT BEKER control 

